The present invention relates generally to a display system and a method for reducing latent images in displays, particularly electro-luminescent displays (ELDs), VFDs, FEDs or CRTs, and assuring that the emissive elements of the display xe2x80x9cagexe2x80x9d more evenly.
The effect of uneven aging of the emissive elements in displays, particularly ELDs displays, is well known. Pixels which are activated more than others will xe2x80x9cagexe2x80x9d sooner than others. As a result, a xe2x80x9clatentxe2x80x9d image formed by the xe2x80x9cagedxe2x80x9d pixels will become visible on the display.
It is known to dim the screen after a period of inactivity by the user, indicated by a lack of input on a user-input device. Alternatively, xe2x80x9cscreen saversxe2x80x9d display moving or changing images which more evenly age the pixels; however, none of these techniques is implemented during use. There may be portions of the display which remain activated for extended periods of time while sufficient activity is occurring in other portions of the screen to prevent the screensaver from activating or the screen to dim.
High resolution reconfigurable displays are being used more frequently in vehicles. Latent images in these displays is a particular problem, since long periods of time without input from a user-input device are not unusual and do not normally mean that the screen can be dimmed or that a xe2x80x9cscreen saverxe2x80x9d can replace the information being displayed. For example, a display which includes vehicle gauges, such as the vehicle speedometer, might operate continuously for hours without a user input, but the information must be displayed constantly. Therefore, the known techniques for reducing latent images are inapplicable.
The present invention provides a display system and method for reducing the latent image caused by uneven aging of the emissive elements in a display. Generally, the display system displays an image at a first position for a first predetermined time period. The display system then displays the image at a second position only a few pixels displaced from the first position for a second predetermined period of time. Preferably, the image is displayed in the first and second positions simultaneously briefly, and then only in the second position. This reduces the noticeability of the transition of the image from the first position to the second position. In the second position, different pixels will be activated, thus more evenly aging pixels on the screen.